Well layers formed from, for example, InGaN are used as active layers in light emitting devices using nitride semiconductors.
When forming well layers, it is important to form high-quality crystals while ensuring that a necessary amount of In is incorporated. If a crystal growth temperature of the well layers is lowered in order to promote the incorporation of the indium (In), thermal stability of the active layer with respect to high temperature processing conducted subsequently will be degraded. A method of controlling the growth temperature and the growth rate when forming the InGaN layers has been proposed. However, there is still room for improvement in the forming of high-quality crystals.